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- As VPlanTransforms replaces some instructions by VPInstructions, then VPInstruction should have costs. - Use legacy model for now. - Computed costs are for the original/replaced instructions to match with what legacy model computed.
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@llvm/pr-subscribers-vectorizers @llvm/pr-subscribers-llvm-transforms Author: Hassnaa Hamdi (hassnaaHamdi) Changes
1 Files Affected:
diff --git a/llvm/lib/Transforms/Vectorize/VPlan.h b/llvm/lib/Transforms/Vectorize/VPlan.h
index a1ff684b2b8017..8813ea3c208b61 100644
--- a/llvm/lib/Transforms/Vectorize/VPlan.h
+++ b/llvm/lib/Transforms/Vectorize/VPlan.h
@@ -1315,6 +1315,9 @@ class VPInstruction : public VPRecipeWithIRFlags,
InstructionCost computeCost(ElementCount VF,
VPCostContext &Ctx) const override {
// TODO: Compute accurate cost after retiring the legacy cost model.
+ // Use legacy cost model for now.
+ if (auto *I = dyn_cast_or_null<Instruction>(getUnderlyingValue()))
+ return Ctx.getLegacyCost(I, VF);
return 0;
}
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| VPCostContext &Ctx) const override { | ||
| // TODO: Compute accurate cost after retiring the legacy cost model. | ||
| // Use legacy cost model for now. | ||
| if (auto *I = dyn_cast_or_null<Instruction>(getUnderlyingValue())) |
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Hi @hassnaaHamdi, I think you should be able to do this without falling back on the legacy cost model. I also plan to put a patch up fairly soon that starts filling this function in properly because it's needed for the early exit work. What instructions were you hitting when getting into this instruction?
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The original instruction was 'or disjoint' and it got replaced by the VPlanTransforms to 'Add' instruction wrapped in VPInstruction.
fhahn
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Could you please add a test case, some more details of what VPInstructions need costs now and how this is related to the change for interleaving?
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Closing this pull request as the work is done by another patch. |
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calculations which may cause choosing VF different than chosen one by legacy cost model.